Mattel got in on the blind packaged toy craze not that long ago by packaging various Hot Wheels in opaque bags and label them as "Mystery Models". However on the back of the package is a small circle where you can see ever so slightly inside. If you finagle the car around enough you can usually see which car is inside.
After looking over this particular assortment I was on the look out for the Chevy Volt...or Super Volt as it was labeled. This wave also included a traditional trading card sized sticker of the included car. Whenever I see these in the store I usually pick one up to see what cars are included in the assortment. I don't know how many different assortments Mattel has released of these Mystery Models, but they are essentially priced the same as the regular Hot Wheels so why not inject some fun into your die-cast car buying?